Lava Hot Springs in southeastern Idaho is a substantial geothermal mineral spring system whose water rises naturally at 113°F and flows at about 34 gallons per second. Long used by Bannock and Shoshone people, the springs later became known to explorers, fur trappers, and westbound travelers in the 1840s and 1850s. John and Mary Hall homesteaded the area in 1890, and in 1902 the Shoshone and Bannock peoples ceded the springs and surrounding acreage to the U.S. government. Rising through Paleozoic quartzite and younger travertine, the mineral-rich waters have shaped the community that took its name from them and remain its defining natural feature.